Breakwater



April 8 1924'.v

J. F. cusHlNG BREAKWATER Filed Jan. 29 1921 Patented Apr. "8, 1924.

Y UNITED STATES JOHN F. CUSHING, 0F CHICAGO, ILLINOIS.

BREAXWATER.

Application led January 29, 1921.

To all whom it may concern Be it known that I, JOHN F. C Us'HlNG, a`

citizen of the United States, residing at Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Breakwaters, of which th following is a specification.

It is the object of -my invention to provide a breakwaterwhich shall be relatively inexpensive, easy to construct and place, permanent and durable under the conditions to which constructions of the kind are commonly exposed. With this in view my improved breakwater comprises a suitable foundation upon which is placed a series of hollow sections or cribs of concrete, keyed or interlocked together at their adjacent ends suitably filled and provided with a monolithic concrete cap extending over any desiredl number of sections.

In the accompanying drawings and in the following specification I have illustrated and described a preferred embodiment of the invention, Fig. 1 representing in transverse verticalsection a breakwater and foundation embodying my invention; Fig. 2 a horizontal section through a portoin of such breakwater, the cribs being shown empty to better disclose the construction; Fig. 3

a longitudinal vertical section through one of the cribs and Fig. 4 an enlar ed vertical transverse section of a detail. ach part is identified by the same reference character wherever it appears in the several views.

Referring first to Fig. 1 the foundation for my improved breakwater is shown at 5 and ma consist of quarry-run rock. The foundation is made of the re uired length and suitable height the latter ldepending on local conditions being in some instances sufficient to bring' the top of the foundation to within about 11 feet of the surface of the water after it has been leveled to receive the superstructure. U on this foundation after leveling are locate a series of concrete cribs 6 hich are interlockedwhen in position at their adjacent ends in a manner which will appear.

he cribs 6 are preferably made at some convenient point on shore where they are allowed to season until the concrete has attained its maximum strength. Each crib comprises sloping side walls 7, .7 and end walls 8, 9, the whole structure being in' the form of a frustrum of a wedge. Each crib is formed on the outside of one end with a Serial No. 441,025.

vertical rib or .key 10 and on the outside of the other end wall with a mating groove or key-Way 11. The concrete walls of the crib may be suitably reinforced, preferably and as shown in the drawings by rods l2 lying in vertical planes the upper ends of which extend beyond the upper edges of the respective walls as at 13 for a purpose which will appear. The respective side walls are formedI with broad bases or sills .14 and wooden struts 15 spaced at suitable intervals longitudinally of the crib extend transversely of the same withtheir ends imbedded in the bases of the side walls. Obviously metal beams could be employed but wooden beams answer the purpose being less expensive and thoroughly permanent since they are always immersed in water and at a considerable distance -below the surface thereof. Tie rods 16 also connect the walls at suitable intervals being preferably arranged directly beneath the beams 15 and having their ends downturned as at 17 to secure a firm grip upon the concrete.

As heretofore stated the cribs are separately molded in advance and then are carried to the foundation on which they are to be placed being readily handl d by ordinary marine equipment. A crib hving aheight of 1222* feet, side walls 12 inches thick end walls 8 inches thick and with a base 15 feet by 11 feet and top 15 feet by 8` feet 8 inches weighs about 50 tons. After the cribs have been placed in position with thebases of the side walls thereof resting upon thefoundation and their end walls interlocked in the manner described quarry-run stone is used to fill the cribs to the top of the walls.,

thereof which in the specific construction described extend after being placed on the foundation about, 1% feet above the surface of the water. The filling rests partially upon the beams and partially directly on the foundation between the beams and the crib structure is thus keyed to the foundation and slipping relative thereto is prevented. After the cribs have been placed in position and filled a cap 18 of concrete is molded thereon extending preferably several `feet above the top edges of the walls and filling and Y interlocking with the latter. This cap is preferably monolithic over several contiguous cribs and the sea side thereof is so inclined as to dissipate as far as possible the shock o f the waves so that the tendency of the latter to move the breakwater is .of stone in the foundation.

rods in the sidewalls extend into the body of the cap andk bind it to the walls. After .the cribs are in place riprap or covering stone in sizes ranging from 300' pounds to 3 tons is laid on the slopingl sides of the stone foundation thus completing the breakwater. A

v My vimproved breakwater is substantially permanent, the exposed surfaces being of stone 'or concrete and the few timbers used being submerged and notfsubject to deterioration.v The breakwaterproper while heavy enoughl for the purpose is'light compared to structures previously used and therefore it is necessary to use a relatively small amount The sea face of the crib'and cap can be so inclined as to reduce the shock of the waves to a minimum and by reason of the inclination the sea f when riding over the breakwater produces a downward thrust counteracting the tendency to overturn the structure. Except for the riprap of which a relatively small quantity is used quarry-run stone of the cheapest character may be employed. Because of the character of the superstructure there is little danger of uneven settlement of the foundav tion after the former is in place and the concrete forming the cap may be made subl stantially impervious to water and hence weatherproof. Moreover yin case of damage to any part of the construction the damaged crib may be removed and a new crib section inserted ata relatively'low cost.

By the use of Athese crib sections which may be filled with smaller and cheaper stone the use of the expensive heavier stoney heretofore required in the breakwaters of this kind for the portions more exposed to the violence of the waves is obviated.

I claim: y 1. A break-water comprlsing a serles of monolithic concrete cribs composed of sidet interand end walls, the end walls havin locking projections and recesses, lil ing in said cribs, and a monolithic concrete cap exim tending over a plurality .of said cribs and partially into the interior thereof to maintain them interlocked.

2. A crib for formingbreakwaters, com'- prising integral concrete side and end walls,

the former being formed with' enlarged bases, spaced beams extending across the beams.

' JOHN F. lCSHING. 

